Lighting system

CROSS REFERENCE TO RELATED APPLICATIONS

0001The present application is a continuation of and claims priority to U.S. patent application Ser. No. 13/119,519 filed May 31, 2011 entitled “Lighting Fixture” and also claims priority to PCT Application No. PCT/JP2009/069423 filed on Nov. 16, 2009 which claims priority to Japanese Patent Application No. 2008-305583 filed Nov. 28, 2008, Japanese Patent Application No. 2008-305584 filed Nov. 28, 2008, Japanese Patent Application No. 2008-305585 filed Nov. 28, 2008, Japanese Patent Application No. 2008-333678 filed Dec. 26, 2008 and Japanese Patent Application No. 2008-333680 filed Dec. 26, 2008. The contents of these applications are incorporated herein by reference in their entirety.

TECHNICAL FIELD

0002Aspects relate to a lighting fixture using a flat lamp device having a cap portion at its one face side and a light source at the other face side.

BACKGROUND

0003Conventionally, a lamp device has been used which uses a GX53-type cap portion standardized by the IEC (International Electrotechnical Commission). The lamp device has a flat lamp device body, the GX53-type cap portion is provided on an upper face side of the lamp device body, a flat light source using a fluorescent lamp, LED or the like is arranged on a lower face side of the lamp device body, and a lighting circuit for lighting the light source is housed inside the lamp device body. On the cap portion, a pair of lamp pins each having a large diameter portion at its top end is projected. The lamp pins of the lamp device are inserted and hooked into a socket device by turning the lamp device, the lamp device is held by the socket device, and power is supplied from the socket device to the lamp pins.

BRIEF DESCRIPTION OF THE DRAWINGS

0004<figref idref="DRAWINGS">FIG. 1</figref> is a cross sectional view of a lighting fixture, in which a lamp device is attached to a socket device, according to a first embodiment of the present invention.

0005<figref idref="DRAWINGS">FIG. 2</figref> is a cross sectional view of the lighting fixture in which the lamp device is detached from the socket device.

0006<figref idref="DRAWINGS">FIG. 3</figref> is a perspective view of the socket device and the lamp device which are detached from each other.

0007<figref idref="DRAWINGS">FIG. 4</figref> is a perspective view of the lamp device.

0008<figref idref="DRAWINGS">FIG. 5</figref> is a cross sectional view of a lighting fixture according to a second embodiment of the present invention.

0009<figref idref="DRAWINGS">FIG. 6</figref> is a perspective view of a vertical cross section of a lighting fixture according to a third embodiment of the present invention.

0010<figref idref="DRAWINGS">FIG. 7</figref> is a perspective view of the partially seen through lighting fixture.

0011<figref idref="DRAWINGS">FIG. 8</figref> is a perspective view of a lighting fixture, which is partially seen through, according, to a fourth embodiment of the present invention.

0012<figref idref="DRAWINGS">FIG. 9</figref> is a cross sectional view of a lighting fixture, in which a socket body of a socket device is arranged at a projecting position, according to a fifth embodiment of the present invention.

0013<figref idref="DRAWINGS">FIG. 10</figref> is a cross sectional view of the lighting fixture in which the socket body of the socket device is arranged at a housing position.

0014<figref idref="DRAWINGS">FIG. 11</figref> is a perspective view showing a state that a lamp device is attached to/detached from the socket body, which is arranged at the projecting position of the socket device.

0015<figref idref="DRAWINGS">FIG. 12</figref> is a perspective view showing a state that the lamp device is attached to the socket body, which is arranged at the projecting position of the socket device.

0016<figref idref="DRAWINGS">FIG. 13</figref> is a perspective view showing a state that the socket body of the socket device is moved to the housing position.

0017<figref idref="DRAWINGS">FIG. 14</figref> is a cross sectional view of a lighting fixture according to a sixth embodiment of the present invention.

0018<figref idref="DRAWINGS">FIG. 15</figref> is a cross sectional view of a lighting fixture according to a seventh embodiment of the present invention.

0019<figref idref="DRAWINGS">FIG. 16</figref> is a side view of a lamp device of a lighting fixture according to an eighth embodiment of the present invention.

0020<figref idref="DRAWINGS">FIG. 17</figref> is a cross sectional view of the lighting fixture of the eighth embodiment.

0021<figref idref="DRAWINGS">FIG. 18</figref> is a cross sectional view of a lighting fixture according to a ninth embodiment of the present invention.

0022<figref idref="DRAWINGS">FIG. 19</figref> is a perspective view of a disassembled lamp device shown in <figref idref="DRAWINGS">FIG. 18</figref>.

0023<figref idref="DRAWINGS">FIG. 20</figref> is a cross sectional view of a lighting fixture according to a tenth embodiment of the present invention.

0024<figref idref="DRAWINGS">FIG. 21</figref> is a perspective view of a lighting fixture according to an eleventh embodiment of the present invention.

0025<figref idref="DRAWINGS">FIG. 22</figref> is a perspective view of a lighting fixture according to a twelfth embodiment of the present invention.

0026<figref idref="DRAWINGS">FIG. 23</figref> is a perspective view of a lamp device and a socket device, which are detached from each other, of a lighting fixture according to a thirteenth embodiment of the present invention.

0027<figref idref="DRAWINGS">FIG. 24</figref> is a plan view of the lamp device shown in <figref idref="DRAWINGS">FIG. 23</figref>.

0028<figref idref="DRAWINGS">FIGS. 25(</figref><i>a</i>) and <b>25</b>(<i>b</i>) are partial cross sectional views each showing a relationship between a lamp pin of the lamp device and a power supplying portion of the socket device.

0029<figref idref="DRAWINGS">FIGS. 26(</figref><i>a</i>) and <b>26</b>(<i>b</i>) are partial cross sectional views each showing a relationship between a signal terminal of the lamp device and a signal transmitting portion of the socket device.

0030<figref idref="DRAWINGS">FIG. 27</figref> is a circuit diagram of the lighting fixture shown in <figref idref="DRAWINGS">FIG. 23</figref>.

0031<figref idref="DRAWINGS">FIG. 28</figref> is a plan view of a lamp device according to a fourteenth embodiment of the present invention.

0032<figref idref="DRAWINGS">FIG. 29</figref> is a plan view of a lamp device according to a fifteenth embodiment of the present invention.

0033<figref idref="DRAWINGS">FIG. 30</figref> is a plan view of a lamp device according to a sixteenth embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

0034When a lamp device is lit, a light source generates heat and heat radiation is necessary. If the heat is also radiated from a cap portion of the lamp device, effective heat radiation performance is obtained.

0035However, in a state that the cap portion of the lamp device is attached to a socket device, the area of the cap portion exposed to the outside becomes small and heat radiation performance is lowered in terms of the attachment structure. Although it is considered that heat is conducted from the cap portion to the socket device side, because a gap is generated between the cap portion and the socket device, and the cap portion and the socket device are not brought into close contact with each other, heat is not efficiently conducted from the cap portion to the socket device side and sufficient heat radiation performance is not obtained.

0036A lighting fixture according to some aspects may include a socket device which holds a cap portion provided at one face side of a flat lamp device and supplies power for lighting a light source arranged at the other face side of the lamp device to the cap portion; a heat radiating body which comes into contact with at least a part of the cap portion of the lamp device held by the socket device; and a pressing body for pressing the cap portion of the lamp device held by the socket device and the heat radiating body in a contact direction.

0037For example, a GX53-type cap structure is used for the cap portion of the lamp device, and a metallic material excellent in thermal conductivity may be used at least at a position where the cap portion comes into contact with the heat radiating body. In addition, a semiconductor light-emitting element such as an LED or an organic EL, a flat discharge lamp, or the like is usable for the light source as long as a flat thin light source is formed. A globe for covering the light source may be attached to the lamp device.

0038For example, a GX53-type cap portion of the lamp device can be attached to the socket device, and the socket device holds the cap portion and can supply power to the cap portion.

0039The heat radiating body is made of, for example, metal excellent in thermal conductivity and heat radiation performance, and may include a heat radiation structure such as fins and may also serve as a metallic reflection body, a fixture body or the like.

0040The pressing body uses, for example, an elastic body such as a spring or rubber, and may press the heat radiating body against the cap portion or press the cap portion against the heat radiating body.

0041The heat radiating body and the pressing body may be separately provided, or a heat radiating body with a pressing function may be singly provided. For example, an integral structure may be employed such as a metallic bellows having a heat radiating function and a pressing function.

0042According to other aspects, a fixture body may be provided on which the socket device is arranged, and the heat radiating body comes into contact with the cap portion of the lamp device and the fixture body.

0043The fixture body and the heat radiating body may be attached in advance so as to come into close contact with each other, or may be pressed against and brought into contact with each other in a contact direction by the pressing body for pressing the cap portion and the heat radiating body in the contact direction.

0044According to yet other aspects, a socket device may include an insertion hole into which a projection portion projected from the center of the cap portion of the lamp device is inserted, and the heat radiating body comes into face-contact with an end face of the projection portion inserted into the socket device.

0045The projection portion of the cap portion may be brought into contact with the heat radiating body by being projected from the socket device, or may be brought into contact with the heat radiating body in a state that the projection portion is not projected from the socket device and the heat radiating body is made to enter the socket device side.

0046Still further, a socket device may include a socket support body and a socket device body to/from which the cap portion of the lamp device can be attached/detached and which is movably supported by the socket support body between a housing position where the socket device body is housed in the socket support body side and a projecting position where the socket device body projects from the socket support body side.

0047The socket support body is, for example, attached to the fixture body or the like of the lighting fixture, and may support the socket device body with any constitution as long as the socket device body is movable between the housing position and the projecting position. A locking structure may also be used which locks the socket device body at the housing position. For the locking structure, a mechanism, for example, a button switch or a knock mechanism of a pen (pencil), can be used which switches a holding position from/to the projecting position to/from the housing position by repeating pressing operations. That is, the socket device body is locked in a manner of being pressed and moved from the projecting position to the housing position by the lamp device, and the lock is cancelled in a manner of slightly pressing the socket device body with the lamp device again so that the socket device body is allowed to move from the housing position to the projecting position. An energizing member such as a spring may be used in a projecting direction of the socket device body.

0048The GX53-type cap portion of the lamp device can be attached to the socket device body, and the socket device body holds the cap portion and can supply power to the cap portion.

0049According to still other aspects, a lamp device may include: a flat lamp device body; a cap portion provided on one face side of the lamp device body; a light source arranged on the other face side of the lamp device body; and a lighting circuit for lighting the light source.

0050The lamp device body and the cap portion may be integrally or separately provided.

0051The lighting circuit may be housed in the lamp device body or arranged together with the light source on the other face side of the lamp device body.

0052Moreover, a globe for covering the light source may be attached to the other face side of the lamp device body.

0053According to some aspects, a lamp device may include: a substrate attachment portion provided on the other face side of the lamp device body; a thermal conduction connection unit for thermally conductively connecting the substrate attachment portion and the cap portion to each other; and a light-emitting module substrate on which semiconductor light-emitting elements as the light source are mounted and which is attached to the substrate attachment portion.

0054The cap portion and substrate attachment portion of the lamp device body may be integrally or separately provided. When the cap portion and the substrate attachment portion are separately provided, these are brought into close contact with each other by the thermal conduction connection unit using a screw-clamping method or screw-engaging method, and the substrate attachment portion side is thermally conductively connected to the cap portion side. When the cap portion and the substrate attachment portion are integrally formed as the thermal conduction connection unit, the substrate attachment portion is thermally conductively connected to the cap portion.

0055In the light-emitting module substrate, for example, a wiring pattern is formed on a metallic substrate via an insulating layer, the semiconductor light-emitting elements are connected onto the wiring pattern. Then, the light-emitting module substrate is closely attached to the substrate attachment portion of the lamp device body with screws, or the like.

0056According to other aspects, a lamp device may include: a substrate attachment portion provided on the other face side of the lamp device body; a projection portion which is formed integrally with the substrate attachment portion and projected from the center of one face side of the substrate attachment portion to the cap portion side; and a light-emitting module substrate on which semiconductor light-emitting elements as the light source are mounted and which is attached to the substrate attachment portion.

0057The inside of the projection portion may be hollow or solid as long as the projection portion is formed integrally with the substrate attachment portion.

0058In the light-emitting module substrate, for example, a wiring pattern is formed on a metallic substrate via an insulating layer, the semiconductor light-emitting elements are mounted onto the wiring pattern. The light-emitting module substrate is closely attached to the substrate attachment portion of the lamp device body with screws, or the like.

0059According to some aspects, a socket device includes: a socket device body for holding the cap portion of the lamp device; a power supplying portion for supplying power to the lamp device held by the socket device body; and a signal transmitting portion for transmitting a signal to the lamp device held by the socket device body, and the lamp device includes: lamp pins which are connectable to the power supplying portion so as to receive power from the power supplying portion of the socket device; signal terminals which are connected to the signal transmitting portion so as to receive a signal transmitted from the signal transmitting portion of the socket device with the lamp pins connected to the power supplying portion; a lighting circuit which receives power from the lamp pins to light the light source; and a control circuit which receives a signal input in the signal terminals to adjust output of the lighting circuit.

0060The socket device body is formed of, for example, insulative synthetic resin, and the power supplying portion and the signal transmitting portion are arranged in the socket device body.

0061The power supplying portion is brought into contact with, and electrically connected to the lamp pins of the lamp device held by the socket device body.

0062The signal transmitting portion is brought into contact with, and electrically connected to the signal terminals of the lamp device held by the socket device body. As long as the signal transmitting portion is brought into contact with, and electrically connectable to the signal terminals in accordance with the shapes of the signal terminals, it may be, for example, arranged inside a hole formed in a surface of the socket device body, provided on the surface of the socket device body or projected from the socket device body.

0063The lamp pin, for example, projects from the cap portion, has a large diameter portion at its top end, is hooked to and held by the socket device by being attached to the socket device, and is electrically connected to the power supplying portion of the socket device so as to receive power.

0064The signal terminal may be, for example, projected from the cap portion, provided on a surface of the cap portion or arranged inside a hole formed in the surface of the cap portion as long as it is brought into contact with and electrically connected to the signal transmitting portion of the socket device with the lamp device held by the socket device. Any signal such as a modulation signal or an RGB signal is adoptable as long as the signal controls output of the light source.

0065Any circuit constitution is applicable to the lighting circuit if it enables output of the lighting circuit to be adjusted.

0066Any constitution is applicable to the control circuit if it enables output of the lighting circuit to be adjusted in accordance with an input signal.

0067According to various aspects, when the cap portion of a lamp device attached to a socket device and the heat radiating body are brought into contact with each other and pressed by a pressing body in a contact direction, a cap portion and a heat radiating body can be reliably brought into close contact with each other, heat can be efficiently conducted from the cap portion to the heat radiating body, and heat of a lamp device can be efficiently radiated from the cap portion.

0068Additionally or alternatively, when the heat radiating body comes into contact with the cap portion of the lamp device and a fixture body, heat can be efficiently conducted from the cap portion to the fixture body and heat of the lamp device can be efficiently radiated from the cap portion.

0069Still further, if an end face of the projection portion, which is inserted into the socket device, of the cap portion and the heat radiating portion comes into face-contact with each other, heat can be efficiently conducted from a projection portion of the cap portion to the heat radiating body.

0070In other examples, if the socket device body is made movable between a housing position where it is housed in a socket support body side and the projecting position where it projects from the socket support side, the lamp device can be easily attached/detached by moving a socket device body to a projecting position even if the socket device is used for a small lighting fixture. In addition, the cap portion of the lamp device and the heat radiating body can be brought into contact with each other by moving the socket device body to the housing position.

0071Moreover, heat of the lamp device can be efficiently radiated from a cap portion by attaching the lamp device to the socket device.

0072According to other aspects, when a light-emitting module substrate is attached to the substrate attachment portion of a lamp device body, and the substrate attachment portion is thermally conductively connected to the cap portion side from the substrate attachment portion side by a thermal conduction connection unit, heat generated by semiconductor light-emitting elements can be efficiently conducted to the cap portion side via a substrate attachment portion and heat radiation performance can be improved.

0073In various examples, if the substrate attachment portion and the projection portion are integrally formed with each other in the lamp device body and a light-emitting module substrate is attached to the other face side of the substrate attachment portion, heat generated by the semiconductor light-emitting elements can be efficiently conducted to a projection portion, which projects from the center of one face side of the substrate attachment portion, via the substrate attachment portion of the lamp device body, heat concentrated at the projection portion can be efficiently radiated from the projection portion, and heat radiation performance can be improved.

0074In still other examples, when power is supplied from a power supplying portion of the socket device to lamp pins of the lamp device and a signal can be transmitted from a signal transmitting portion of the socket device to signal terminals of the lamp device with the power supplying portion and the lamp pins connected to each other, the lamp device, by attaching the lamp device to the socket device, can receive a signal from the socket device and can adjust output of the lighting circuit in accordance with the signal.

0075Hereinafter, embodiments will be described with reference to the drawings.

0076<figref idref="DRAWINGS">FIGS. 1 to 4</figref> show a first embodiment, <figref idref="DRAWINGS">FIG. 1</figref> is a cross sectional view of a lighting fixture in which a lamp device is attached to a socket device, <figref idref="DRAWINGS">FIG. 2</figref> is a cross sectional view of the lighting fixture in which the lamp device is detached from the socket device, <figref idref="DRAWINGS">FIG. 3</figref> is a perspective view of the socket device and the lamp device which are detached from each other, and <figref idref="DRAWINGS">FIG. 4</figref> is a perspective view of the lamp device.

0077A lighting fixture <b>11</b> is, for example, a downlight, and includes: a fixture body <b>12</b> as a heat radiating body; a socket device <b>13</b> attached to the fixture body <b>12</b>; and a flat lamp device <b>14</b> attachable to/detachable from the socket device <b>13</b>. Moreover, regarding a directional (vertical) relationship of these body and devices, description will be made below by setting a state, where the flat lamp device <b>14</b> is horizontally attached, as a reference and defining a cap portion side, which is one face side of the lamp device <b>14</b>, as an upper face side and a light source side, which is the other face side of the lamp device <b>14</b>, as a lower face side.

0078The fixture body <b>12</b> is made of metal, formed so as to serve as a reflection body as well, and has a circular flat plate portion <b>17</b> and a reflecting plate portion <b>18</b> curvedly bent downward from a circumferential portion of the flat plate portion <b>17</b>. An opening portion <b>19</b> is formed on a lower face of the reflecting plate portion <b>18</b>.

0079The socket device <b>13</b> has a cylindrical insulative socket device body <b>21</b> made of synthetic resin, and an insertion hole <b>22</b> is formed so as to vertically penetrate the center of the socket device body <b>21</b>. A pair of projection portions <b>23</b> is projected on an inner face of the insertion hole <b>22</b> so as to extend to the center of the insertion hole <b>22</b>.

0080A pair of socket portions <b>24</b> are formed at a lower face of the socket device body <b>21</b>. A connection hole <b>25</b> is formed in each socket portion <b>24</b>, and a bracket (not shown) for supplying power is arranged inside the connection holes <b>25</b>. The connection holes <b>25</b> are arc-shaped grooves located rotationally symmetric with respect to the center of the socket device body <b>21</b>, and an enlarged diameter portion <b>26</b> is formed at one end of each arc-shaped groove.

0081A plurality of recess portions <b>27</b> are formed on the lower face of the socket device body <b>21</b>, a screw shaft <b>29</b> of a screw <b>28</b> is inserted and arranged in each recess portion <b>27</b> from the fixture body <b>12</b>, and a nut <b>31</b> is screw-engaged with the screw shaft <b>29</b> via an elastic body <b>30</b> as a pressing body made of, for example, rubber. The socket device <b>13</b> is attached to the flat plate portion <b>17</b> of the fixture body <b>12</b> with these screws <b>28</b>, elastic bodies <b>30</b> and nuts <b>31</b>.

0082The lamp device <b>14</b> includes: a flat lamp device body <b>34</b>; a plurality of LEDs <b>35</b> which are semiconductor light-emitting elements as a light source arranged on a lower face side of the lamp device body <b>34</b>; a globe <b>36</b> for covering the LEDs <b>35</b>; and a lighting circuit <b>37</b> for lighting the LEDs <b>35</b>, and is thinly formed so that the size of its height direction is smaller than the size of its horizontal direction.

0083The lamp device body <b>34</b> is formed of, for example, insulative synthetic resin or metal such as aluminum excellent in heat radiation performance. A GX53-type cap portion <b>38</b> is formed on an upper face side which is one face side of the lamp device body <b>34</b>, a flat substrate attachment portion <b>39</b>, to which the LEDs <b>35</b> are attached, is formed on the lower face side which is the other face side thereof, and a housing portion <b>40</b> for housing the lighting circuit <b>37</b> is formed in the lamp device body <b>34</b>.

0084In the cap portion <b>38</b>, an annular contact face <b>41</b> coming into contact with a lower face of the socket device <b>13</b> is formed, and a columnar projection portion <b>42</b>, which can be inserted into the insertion hole <b>22</b> of the socket device <b>13</b>, is projected from the center of the contact face <b>41</b>. The projection size of the projection portion <b>42</b> is larger than the height of the socket device <b>13</b>, that is, the depth of the insertion hole <b>22</b>, and an end face <b>43</b> of the projection portion <b>42</b> penetrates the insertion hole <b>22</b> and projects when the lamp device <b>14</b> is attached to the socket device <b>13</b>.

0085A pair of metallic lamp pins <b>44</b> each having conductivity is projected on the contact face <b>41</b>. A large diameter portion <b>45</b> is formed at a top end of the lamp pin <b>44</b>. The large diameter portion <b>45</b> of each lamp pin <b>44</b> is inserted into the enlarged diameter portion <b>26</b> of each connection hole <b>25</b> of the socket device <b>13</b>, the lamp pin <b>44</b> is moved from the enlarged diameter portion <b>26</b> to the connection hole <b>25</b> by turning the lamp device <b>14</b> and electrically connected to a bracket, the large diameter portion <b>45</b> is hooked to the bracket or an edge portion of the connection hole <b>25</b>, the lamp device <b>14</b> is held by the socket device <b>13</b>. Moreover, when the lamp device body <b>34</b> is made of metal, each lamp pin <b>44</b> is attached to the lamp device body <b>34</b> via an insulating member.

0086A pair of guide grooves <b>46</b>, with which the projection portions <b>23</b> of the socket device <b>13</b> are engaged, is formed on a peripheral face of the projection portion <b>42</b>. The guide groove <b>46</b> has an introduction groove portion <b>47</b> opened to the end face <b>43</b> of the projection portion <b>42</b>, an inclined groove portion <b>48</b> inclined from the introduction groove portion <b>47</b> and a holding groove portion <b>49</b> horizontally extending from the inclined groove portion <b>48</b>. The introduction groove portions <b>47</b> of the guide grooves <b>46</b> are aligned with the projection portions <b>23</b> of the socket device <b>13</b>, the lamp device <b>14</b> is raised and turned in an attachment direction, the projection portions <b>23</b> and the inclined groove portions <b>48</b> are engaged with each other, the lamp device <b>14</b> is moved relatively upward, the socket device <b>13</b> is moved relatively downward, and engagement positions of the projection portions <b>23</b> with the holding groove portions <b>49</b> become, as a whole, an attachment position of the lamp device <b>14</b> to the socket device <b>13</b>.

0087The plurality of LEDs <b>35</b> are mounted on a lower face side of a light-emitting module substrate <b>50</b>. An upper face of the light-emitting module substrate <b>50</b> is brought into close face-contact with and attached to the substrate attachment portion <b>39</b> on the lamp device body <b>34</b>. The light-emitting module substrate <b>50</b> is formed in a manner of, for example, forming a wiring pattern on a metallic substrate via an insulating layer and mounting the LEDs <b>35</b> on the wiring pattern, and attached to the substrate attachment portion <b>39</b> on the lamp device body <b>21</b> so as to come into close contact therewith screws, or the like. A light-emitting module is constituted by the plurality of LEDs <b>35</b> and the light-emitting module substrate <b>50</b>.

0088The globe <b>36</b> is formed of glass or synthetic resin having transparency or light-diffuseness.

0089The lighting circuit <b>37</b> includes a lighting circuit substrate (not shown) and lighting circuit components (not shown) mounted on the lighting circuit, each lamp pin <b>44</b> is electrically connected to an input portion of the lighting circuit substrate via a lead wire or the like, and the light-emitting module substrate <b>50</b> is electrically connected to output portions of the lighting circuit substrate via lead wires or the like. When the lamp device body <b>34</b> is made of metal, the lighting circuit substrate and lighting circuit components are housed in the housing portion <b>40</b> of the lamp device body <b>34</b> via an insulating material.

0090Next, action of the lighting fixture <b>11</b> of the first embodiment will be described.

0091As shown in <figref idref="DRAWINGS">FIG. 2</figref>, the socket device <b>13</b>, to which the lamp device <b>14</b> is not yet attached, is pushed upward by pressing of the elastic body <b>30</b>, and an upper face of the socket device <b>13</b> is brought into contact with the flat plate portion <b>17</b> of the fixture body <b>12</b>.

0092In order to attach the lamp device <b>14</b> to the socket device <b>13</b>, the projection portion <b>42</b> of the lamp device <b>14</b> is inserted into the insertion hole <b>22</b> of the socket device <b>13</b> from below, the introduction groove portions <b>47</b> of the guide grooves <b>46</b> provided on the projection portion <b>42</b> of the lamp device <b>14</b> are aligned with the projection portions <b>23</b> of the socket device <b>13</b>, the lamp pins <b>44</b> of the lamp device <b>14</b> are aligned with the enlarged diameter portions <b>26</b> of the connection holes <b>25</b> of the socket device <b>13</b>, and the lamp device <b>14</b> is pushed upward and turned in the attachment direction. By pushing upward and turning the lamp device <b>14</b> in the attachment direction, the projection portions <b>23</b> and the inclined groove portions <b>48</b> of the guide grooves <b>46</b> are engaged with each other, the lamp device <b>14</b> is moved upward, and the end face <b>43</b> of the projection portion <b>23</b> comes into contact with the flat plate portion <b>17</b> of the fixture body <b>12</b>. Further, by turning the lamp device <b>14</b> in the attachment direction, the socket device <b>13</b> moves downward against the pressing of the elastic body <b>30</b> in relation to the lamp device <b>14</b> which is restricted from moving upward by contact with the flat plate portion <b>17</b> of the fixture body <b>12</b>. As shown in <figref idref="DRAWINGS">FIG. 1</figref>, by engagement of the projection portions <b>23</b> and the holding groove portions <b>49</b> of the guide grooves <b>46</b>, the lamp device <b>14</b> is attached to the socket device <b>13</b> at the attachment position, and the lamp pins <b>44</b> are electrically brought into contact with the brackets of the socket device <b>13</b>.

0093Since the socket device <b>13</b> is pushed upward by the pressing of the elastic body <b>30</b> with the lamp device <b>14</b> attached to the socket device <b>13</b>, the end face <b>43</b> of the projection portion <b>42</b> from the upper face of the socket device <b>13</b> is pressed against and brought into close face-contact with the flat plate portion <b>17</b> of the fixture body <b>12</b>.

0094Therefore, when the LEDs <b>35</b> of the lamp device <b>14</b> are lit, heat generated by the LEDs <b>35</b> is conducted from the light-emitting module substrate <b>50</b> to the cap portion <b>38</b>, efficiently conducted from the end face <b>43</b> of the projection portion <b>42</b> to the fixture body <b>12</b> and efficiently radiated into air or the like.

0095Accordingly, even in the state that the lamp device <b>14</b> is attached to the socket device <b>13</b> of the fixture body <b>12</b>, heat of the lamp device <b>14</b> can be sufficiently radiated from the cap portion <b>38</b>. Therefore, the lamp device <b>14</b> obtains sufficient heat radiation performance, can restrict the temperature of the LED <b>35</b> from rising, and can prevent the LED from being thermally deteriorated and having a short life and, in some cases, light-emitting efficiency from being lowered.

0096Moreover, at least either the flat plate portion <b>17</b> of the fixture body <b>12</b> or the end face <b>43</b> of the lamp device <b>14</b> may be subjected, for improvement in thermal conductivity from the cap portion <b>38</b> to the fixture body <b>12</b>, to surface treatment such as polishing for raising smoothness, or a thermally conductive member such as a gel material or heat radiation sheet having flexibility or elasticity and excellent in thermal conductivity may be arranged on at least either the flat plate portion <b>17</b> or the end face <b>43</b>.

0097In addition, for other embodiments described below, the same symbols are attached to the same structures as those of the first embodiment, and description thereof will be omitted.

0098Next, <figref idref="DRAWINGS">FIG. 5</figref> is a cross sectional view of a lighting fixture according to a second embodiment.

0099The fixture body <b>12</b> includes: a cylindrical portion <b>52</b>; a top plate portion <b>53</b> provided on an upper face of the cylindrical portion <b>52</b>; and a reflecting plate portion <b>54</b> projecting obliquely outward from a lower portion of the cylindrical portion <b>52</b>.

0100The socket device <b>13</b> is fixed to a lower portion side of the cylindrical portion <b>52</b> of the fixture body <b>12</b>, and a heat radiating plate <b>55</b> as a heat radiating body and a spring <b>56</b> as a pressing body are arranged in a space between the upper face of the socket device <b>13</b> and the top plate portion <b>53</b> of the fixture body <b>12</b>.

0101The heat radiating plate <b>55</b> is made of metal, and includes: a contact portion <b>57</b>, which is brought into face-contact with the end face <b>43</b> of the projection portion <b>42</b> projecting from the cap portion <b>38</b> of the lamp device <b>14</b> and has an approximately overturned U-shaped cross section, at its center portion; and both ends led outward from the fixture body <b>12</b>, and is arranged vertically movably in relation to the fixture body <b>12</b>. Fins or the like may be provided at both ends of the heat radiating plate <b>55</b> so as to raise the heat radiation effect.

0102The spring <b>56</b> is arranged, in a compressed manner, between an upper face of the contact portion <b>57</b> of the heat radiating plate <b>55</b> and the top plate portion <b>53</b> of the fixture body <b>12</b>, and presses the heat radiating plate <b>55</b> downward.

0103By attaching the lamp device <b>14</b> to the socket device <b>13</b>, the contact portion <b>57</b> of the heat radiating plate <b>55</b> is brought into contact with the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b> and the contact portion <b>57</b> of the heat radiation plate <b>55</b> is pressed against and brought into close face-contact with the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b> by the spring <b>56</b>.

0104Therefore, when the lamp device <b>14</b> is lit, heat generated by the LEDs <b>35</b> is conducted from the light-emitting module substrate <b>50</b> to the cap portion <b>38</b>, efficiently conducted from the end face <b>43</b> of the projection portion <b>42</b> to the heat radiating plate <b>55</b> and efficiently radiated into air or the like.

0105Accordingly, even in the state that the lamp device <b>14</b> is attached to the socket device <b>13</b> of the fixture body <b>12</b>, heat of the lamp device <b>14</b> can be efficiently radiated from the cap portion <b>38</b>.

0106Although the spring <b>56</b> is used as the pressing body, the heat radiating plate <b>55</b> may be brought into close contact with the end face <b>43</b> of the projection portion <b>42</b> by elasticity of the heat radiating plate <b>55</b> itself. In this case, the spring <b>56</b> may be removed and the heat radiating plate <b>55</b> can be made to serve as the pressing body.

0107Next, <figref idref="DRAWINGS">FIG. 6</figref> is a perspective view of a cross section of a part of a lighting fixture and <figref idref="DRAWINGS">FIG. 7</figref> is a perspective view of a partially seen through lighting fixture, according to a third embodiment.

0108A lighting fixture <b>12</b> of the third embodiment has the same structure as that of the second embodiment. A heat radiating plate <b>60</b> as a heat radiating body and a spring <b>61</b> as a pressing body are arranged in the space between the upper face of the socket device <b>13</b> and the top plate portion <b>53</b> of the fixture body <b>12</b>.

0109The heat radiating plate <b>60</b> is made of metal, for example, copper, and formed in a ring shape. That is, the heat radiating plate <b>60</b> includes: a flat contact portion <b>62</b>, which comes into face-contact with the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b> of the lamp device <b>14</b>, at its lower face; a flat contact portion <b>63</b>, which comes into face-contact with the fixture body <b>12</b>, at its upper face; and curved side face portions <b>64</b> which are formed between both sides of the contact portions <b>62</b> and <b>63</b> so as to make expansion and contraction of an interval between the contact portions <b>62</b> and <b>63</b>.

0110The spring <b>61</b> is, in a compressed manner, arranged inside the heat radiating plate <b>60</b> and between the upper and lower contact portions <b>62</b> and <b>63</b>.

0111By attaching the lamp device <b>14</b> to the socket device <b>13</b>, the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b> projects from the upper face of the socket device <b>13</b> and comes into contact with the contact portion <b>62</b> of the lower face of the heat radiating plate <b>60</b>. By the spring <b>61</b> arranged inside the heat radiating plate <b>60</b>, the contact portion <b>62</b> of the lower face of the heat radiating plate <b>60</b> is pressed against and brought into close face-contact with the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b>, and the contact portion <b>63</b> of the upper face of the heat radiating plate <b>60</b> is pressed against and brought into close face-contact with the fixture body <b>12</b>.

0112Therefore, when the lamp device <b>14</b> is lit, heat generated by the LEDs <b>35</b> is conducted from the light-emitting module substrate <b>50</b> to the cap portion <b>38</b>, efficiently conducted from the end face <b>43</b> of the projection portion <b>42</b> to the heat radiating plate <b>60</b>, efficiently conducted from the heat radiating plate <b>60</b> to the fixture body <b>12</b> and efficiently radiated from the fixture body <b>12</b> into air or the like.

0113Accordingly, even in the state that the lamp device <b>14</b> is attached to the socket device <b>13</b> on the fixture body <b>12</b>, heat of the lamp device <b>14</b> can be efficiently radiated from the cap portion <b>38</b>.

0114Moreover, although the spring <b>61</b> is used as the pressing body, the heat radiating plate <b>60</b> may be brought into close contact with the end face <b>43</b> of the projection portion <b>42</b> by elasticity of the heat radiating plate <b>60</b> itself. In this case, the spring <b>61</b> may be removed and the heat radiating plate <b>60</b> can be made to serve as the pressing body.

0115Next, <figref idref="DRAWINGS">FIG. 8</figref> is a perspective view of a partially seen through lighting fixture, according to a fourth embodiment.

0116A lighting fixture <b>12</b> of the fourth embodiment has the same structure as those of the second and third embodiments. A heat radiating member <b>67</b> serving as a heat radiating body and a pressing body is arranged in the space between the upper face of the socket device <b>13</b> and the top plate portion <b>53</b> of the fixture body <b>12</b>. The heat radiating member <b>67</b> is made of metal, for example, copper, formed in the shape of a cylindrical bellows and arranged between the upper face of the socket device <b>13</b> and the top plate portion <b>53</b> of the fixture body <b>12</b> with the member <b>67</b> compressed.

0117By attaching the lamp device <b>14</b> to the socket device <b>13</b>, the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b> projects from the upper face of the socket device <b>13</b> and comes into contact with a lower portion of the heat radiating member <b>67</b>. By elasticity of the heat radiating member <b>67</b>, the lower portion of the heat radiating member <b>67</b> is brought into close contact with the end face <b>43</b> of the projection portion <b>42</b> and an upper portion of the heat radiating member <b>67</b> is brought into close contact with the fixture body <b>12</b>.

0118Therefore, when the lamp device <b>14</b> is lit, heat generated by the LEDs <b>35</b> is conducted from the light-emitting module substrate <b>50</b> to the cap portion <b>38</b>, efficiently conducted from the end face <b>43</b> of the projection portion <b>42</b> to the heat radiating member <b>67</b>, efficiently conducted from the heat radiating member <b>67</b> to the fixture body <b>12</b> and efficiently radiated from the fixture body <b>12</b> into air or the like.

0119Accordingly, even in the state that the lamp device <b>14</b> is attached to the socket device <b>13</b> of the fixture body <b>12</b>, heat of the lamp device <b>14</b> can be efficiently radiated from the cap portion <b>38</b>.

0120Further, since the one heat radiating member <b>67</b> serves as the heat radiating body and the pressing body, the number of components can be reduced.

0121Moreover, it is allowed that the reflecting plate portion <b>54</b> is separated from the fixture body <b>12</b> and detachably attached to the lamp device <b>14</b>. Therefore, heat of the lamp device <b>14</b> is conducted to the reflecting plate portion <b>54</b>, and heat radiation performance can be improved. Further, the lamp device <b>14</b> can be attached to/detached from the socket device <b>13</b> by handling the reflecting plate portion <b>54</b> and operability can be improved.

0122Next, <figref idref="DRAWINGS">FIGS. 9 to 13</figref> show a lighting fixture according to a fifth embodiment. <figref idref="DRAWINGS">FIG. 9</figref> is a cross sectional view of the lighting fixture in which a socket body of the socket device is arranged at a projecting position. <figref idref="DRAWINGS">FIG. 10</figref> is a cross sectional view of the lighting fixture in which the socket body of the socket device is arranged at a housing position. <figref idref="DRAWINGS">FIG. 11</figref> is a perspective view showing a state before the lamp device <b>11</b> is attached to the socket body, which is arranged at the projecting position of the socket device. <figref idref="DRAWINGS">FIG. 12</figref> is a perspective view showing a state that the lamp device is attached to the socket body, which is arranged at the projecting position of the socket device. <figref idref="DRAWINGS">FIG. 13</figref> is a perspective view showing a state that the socket body of the socket device is moved to the housing position.

0123The socket device <b>13</b> includes a socket support body <b>71</b> attached to the flat plate portion <b>17</b> of the fixture body <b>12</b> and a socket device body <b>21</b> supported vertically movably in relation to the socket support body <b>71</b>.

0124The socket support body <b>71</b> is made of, for example, metal, and opened downward, and the socket device body <b>21</b> is fitted in the socket support body <b>71</b> so as to be vertically movable. That is, by the socket support body <b>71</b>, the socket device body <b>21</b> is movably supported between the housing position where the socket device body <b>21</b> is housed in the socket support body <b>71</b> and the projecting position where the body <b>21</b> projects downward from the socket support body <b>71</b>.

0125Springs <b>72</b> as an energizing unit for energizing the socket device body <b>21</b> to the projecting position are arranged between the socket support body <b>71</b> and the socket device body <b>21</b>, and a stopper (not shown) for regulating projection of the socket device body <b>21</b> at the projecting position is provided on a socket support body <b>71</b>.

0126A locking unit (not shown) for locking the socket device body <b>21</b> at the housing position is provided between the socket support body <b>71</b> and the socket device body <b>21</b>. The locking unit functioning like, for example, a push button switch, locks the socket device body <b>21</b> to the housing position by pushing upward and moving the socket device body <b>21</b> from the projecting position to the housing position with use of the lamp device <b>14</b>. In addition, the locking unit unlocks the socket device body <b>21</b> by further slightly pushing upward the socket device body <b>21</b> with use of the lamp device <b>14</b> and allows the socket device body <b>21</b> to move down from the housing position to the projecting position. Although action of such a locking unit can be realized by using a spring for energizing the socket device body <b>21</b> into the socket support body <b>71</b>, and a cam mechanism for regulating a rotation angle or the like, another well-known mechanism may be used as the locking unit.

0127A plurality of columnar ribs <b>73</b> each having a vertical axis are projected on an inner circumferential portion of the socket support body <b>71</b>, groove portions <b>74</b> each of which has a semicircular cross section and engages with each rib <b>73</b> are vertically formed at a plurality of locations of an outer circumferential portion of the socket device body <b>21</b>, and a locking member <b>75</b> is arranged aside of each groove portion <b>74</b> so as to be capable of entering/exiting the groove portion <b>74</b>. The locking member <b>75</b> enters/exits the groove portion <b>74</b> in conjunction with turning operation of the lamp device <b>14</b> when the lamp device <b>14</b> is attached to/detached from the socket device body <b>21</b> held at the projecting position, and can be constituted by, for example, the below-described cam mechanism coming into contact with the lamp pin <b>44</b>. In a state that the lamp device <b>14</b> is not attached to the socket device body <b>21</b> located at the projecting position, the locking member <b>75</b> enters the groove portion <b>74</b> and, when the socket device body <b>21</b> starts moving from the projecting position to the housing position, comes into contact with the rib <b>73</b> so as to restrict the movement of the socket device body <b>21</b>. In a state that the lamp device <b>14</b> is connected to the socket device body <b>21</b> located at the projecting position, the locking member <b>75</b> exits the groove portion <b>74</b> and allows the socket device body <b>21</b> to move from the projecting position to the housing position. Accordingly, the ribs <b>73</b>, the groove portions <b>74</b>, the locking members <b>75</b> or the like constitute lock units <b>76</b> which allow the socket device body <b>21</b>, to which the lamp device <b>14</b> is attached, to move between the projecting position and the housing position and to restrict the socket device body <b>21</b>, to which the lamp device <b>14</b> is not attached, from moving from the projecting position to the housing position.

0128In a state that the socket device body <b>21</b> moves to the housing position, each rib <b>73</b> is positioned in a region, where the locking member <b>75</b> enters, in the groove portion <b>74</b>, the locking member <b>75</b> cannot enter the groove portion <b>74</b>, the lamp device <b>14</b> interlocking with the locking members <b>75</b> cannot be turned in a direction of being detached from the socket device body <b>21</b>. Accordingly, the ribs <b>73</b>, the groove portions <b>74</b>, the locking members <b>75</b> or the like constitute a lamp device holding unit <b>77</b> for restricting the lamp device <b>14</b> from coming off from the socket device body <b>21</b> moved to the housing position.

0129A thermally conductive member <b>78</b>, to which the lamp device <b>14</b> is thermally conductively connected by movement of the socket device body <b>21</b>, to which the lamp device <b>14</b> is attached, to the housing position, is arranged on the socket support body <b>71</b>.

0130As shown in <figref idref="DRAWINGS">FIGS. 9 and 11</figref>, the socket device body <b>21</b>, to which the lamp device <b>14</b> is not attached, of the socket device <b>13</b> is projected downward in relation to the socket support body <b>71</b> (located at the projecting position), located in the vicinity of the opening portion <b>19</b> side of a lower face of the fixture body <b>12</b> and held at the projecting position by energization of the springs <b>72</b>.

0131The locking member <b>75</b> on the socket device body <b>21</b> is located below the rib <b>73</b> and enters the groove portion <b>74</b>, and an upper face of the locking member <b>75</b> faces a top end face of the rib <b>73</b>.

0132In order to attach the lamp device <b>14</b> to the socket device <b>13</b>, the lamp device <b>14</b> is raised so that each lamp pin <b>44</b> of the lamp device <b>14</b> is aligned with and inserted into the enlarged diameter portion <b>26</b> of each connection hole <b>25</b> of the socket device body <b>21</b>. Even if each lamp pin <b>44</b> of the lamp device <b>14</b> is not aligned with the enlarged diameter portion <b>26</b> of each connection hole <b>25</b> of the socket device body <b>21</b> and pushes upward the socket device body <b>21</b>, each locking member <b>75</b> comes into contact with the top end face of the rib <b>73</b>. Accordingly, the socket device body <b>21</b> is prevented from moving upward to the housing position, and thus the lamp device <b>14</b> can be prevented from being hardly attached to the socket device <b>13</b>.

0133After each lamp pin <b>44</b> of the lamp device <b>14</b> is inserted into the enlarged diameter portion <b>26</b> of the connection hole <b>25</b> of the socket device body <b>21</b>, the lamp device <b>14</b> is turned in the attachment direction and attached to the socket device body <b>21</b> as shown in <figref idref="DRAWINGS">FIG. 12</figref>.

0134When the lamp device <b>14</b> is thus attached to the socket device body <b>21</b>, the socket device body <b>21</b> is located at the projecting position and in the vicinity of the opening portion <b>19</b> side of the lower face of the fixture body <b>12</b>. Therefore, a space into which fingers are inserted can be formed between a circumferential portion of the lamp device <b>14</b> to be attached to the socket device body <b>21</b> and the reflecting plate portion <b>18</b> of the fixture body <b>12</b>, and the lamp device <b>14</b> can be, being held by hand, easily attached to the socket device body <b>21</b>.

0135By turning the lamp device <b>14</b> in the attachment direction, the locking members <b>75</b> exit the groove portions <b>74</b> in accordance therewith, and the socket device body <b>21</b> is allowed to move to the housing position.

0136After the lamp device <b>14</b> is attached to the socket device body <b>21</b>, the lamp device <b>14</b> is pushed upward, and thus the socket device body <b>21</b> is pushed upward to the housing position and the lamp device <b>14</b> can be held at a predetermined attachment position in the fixture body <b>12</b> as shown in <figref idref="DRAWINGS">FIGS. 10 and 13</figref>. The socket device body <b>21</b> moved to the housing position is locked by the locking unit.

0137The socket device body <b>21</b> to which the lamp device <b>14</b> is attached is moved to the housing position, and thus the cap portion <b>38</b> of the lamp device <b>14</b> is brought into close face-contact with the thermally conductive member <b>78</b> and the lighting fixture <b>11</b> is thereby in a use state.

0138Since the cap portion <b>38</b> of the lamp device <b>14</b> is brought into close face-contact with the thermally conductive member <b>78</b> although heat is generated when the LEDs <b>35</b> of the lamp device <b>14</b> are lit, the heat generated from the lamp device <b>14</b> is efficiently conducted to the fixture body <b>12</b> via the thermally conductive member <b>78</b> and heat radiation performance of the lamp device <b>14</b> can be improved.

0139In the state that the socket device body <b>21</b> is located at the housing position, each rib <b>73</b> is positioned in the region, where the locking member <b>75</b> enters, in the groove portion <b>74</b>, the locking member <b>75</b> cannot enter the groove portion <b>74</b>, and the lamp device <b>14</b> interlocking with the locking members <b>75</b> cannot be turned in the direction of being detached from the socket device body <b>21</b>.

0140On the other hand, in the case of detaching the lamp device <b>14</b>, the socket device body <b>21</b> located at the housing position is slightly pushed upward via the lamp device <b>14</b> so that the lock by the locking unit is canceled, and thus moved downward to the projecting position together with the lamp device <b>14</b> by the energization of the spring <b>72</b>.

0141When the socket device body <b>21</b> is moved downward to the projecting position, the lamp device <b>14</b> is turned in the detachment direction and then moved downward, and thus the lamp pins <b>44</b> of the lamp device <b>14</b> are pulled out from the connection holes <b>25</b> of the socket device body <b>21</b> and the lamp device <b>14</b> can be detached from the socket device body <b>21</b>.

0142When the socket device body <b>21</b> is moved downward to the projecting position, each locking member <b>75</b> on the socket device body <b>21</b> moves further downward than the rib <b>73</b> and thus enters the groove portion <b>74</b> in accordance with turning of the lamp device <b>14</b> in the detachment direction, and the socket device body <b>21</b> is restricted from moving to the housing position.

0143The socket device body <b>21</b> of the socket device <b>13</b> can thus be moved between the housing position where it is housed in the socket support body <b>71</b> side and the projecting position where it projects from the socket support <b>71</b> side. Accordingly, even if the socket device <b>13</b> is used for a small lighting fixture, the socket device body <b>21</b> is moved to the projecting position in relation to the socket support body <b>71</b> attached to the fixture body <b>12</b> side, and thus the lamp device <b>14</b> can be, with the circumferential portion of the lamp device <b>14</b> gripped, easily detached.

0144By the lamp device holding unit <b>77</b>, the lamp device <b>14</b> is restricted from coming off from the socket device body <b>21</b> moved to the housing position and thus the lamp device <b>14</b> attached to the socket device <b>13</b> can be prevented from coming off from the socket device <b>13</b>, and, when the lamp device <b>14</b> is detached, the socket device <b>13</b> can be reliably held at the projecting position and the lamp device <b>14</b> can be easily attached.

0145Next, <figref idref="DRAWINGS">FIG. 14</figref> is a cross sectional view of a lighting fixture according to a sixth embodiment.

0146The whole lamp device body <b>34</b> of the lamp device <b>14</b> is formed of metal such as aluminum excellent in heat radiation performance, made of, for example, an aluminum die casting, and divided into a cap side metallic part <b>81</b> constituting the cap portion <b>38</b> and a light source side metallic part <b>82</b> constituting the substrate attachment portion <b>39</b>. The cap side metallic part <b>81</b> is formed in the shape of a disk opened downward, and a contact face <b>84</b> with which the light source side metallic part <b>82</b> comes into contact is formed at an end face of an annular outer circumferential portion <b>83</b> of the metallic part <b>81</b>. The light source side metallic part <b>82</b> is formed in a flat disk shape so as to close an opening of a lower face of the cap side metallic part <b>81</b>, and an upper face of a circumferential portion of the metallic part <b>82</b> can come into contact with the contact face of the cap side metallic part <b>81</b>. The light source side metallic part <b>82</b> is fixed to the cap side metallic part <b>81</b> with a plurality of screws <b>85</b> as a thermal conduction connection unit, and is thermally conductively closely connected to the cap portion side metallic part <b>81</b> from the light source side metallic part <b>82</b>.

0147An insulating member <b>86</b> is interposed between the cap side metallic part <b>81</b> of the lamp device body <b>34</b> and the lamp pin <b>44</b>.

0148The light-emitting module substrate <b>50</b> on which the plurality of LEDs <b>35</b> are mounted is closely attached to the substrate attachment portion <b>39</b> of the lamp device body <b>34</b>.

0149The lighting circuit <b>37</b> includes a lighting circuit substrate <b>89</b> and lighting circuit parts <b>90</b> mounted on the lighting circuit substrate <b>89</b>, each lamp pin <b>44</b> is electrically connected to an input portion of the lighting circuit substrate <b>89</b> via a lead wire <b>91</b>, and the light-emitting module substrate <b>50</b> is electrically connected to output portions of the lighting circuit substrate <b>89</b> via lead wires or the like. The lighting circuit substrate <b>89</b> is housed in the housing portion <b>40</b> of the lamp device body <b>34</b> via an insulating material (not shown).

0150In the case where the lamp device <b>14</b> is attached to the socket device <b>13</b>, the outer circumferential portion <b>83</b> of the lamp device body <b>34</b> is thermally conductively brought into contact with the reflecting plate portion <b>18</b> of the fixture body <b>12</b>, and the end face <b>43</b> of the projection portion <b>42</b> of the lamp device body <b>34</b> is thermally conductively brought into contact with the flat plate portion <b>17</b> of the fixture body <b>12</b>.

0151Therefore, heat generated from the LEDs <b>35</b> is efficiently radiated when the LEDs <b>35</b> of the lamp device <b>14</b> are lit. That is, since the light-emitting module attachment portion <b>50</b> is brought into close contact with the substrate attachment portion <b>39</b> of the metallic lamp device body <b>34</b> and the substrate attachment portion <b>39</b> is thermally conductively connected to the cap portion <b>38</b> side with the screws <b>85</b> as the thermal conduction connection unit, the heat generated from the LEDs <b>35</b> can be efficiently conducted to the cap portion <b>38</b> side via the substrate attachment portion <b>39</b>. The heat conducted to the cap portion <b>38</b> is conducted to the fixture body <b>12</b> coming into contact with the cap portion <b>38</b> and can be efficiently radiated from the fixture body <b>12</b>.

0152Moreover, a plurality of slits for dividing the reflecting plate portion <b>18</b> in a circumferential direction may be provided in the reflecting plate portion <b>18</b>, and the outer circumferential portion <b>83</b> of the lamp device body <b>34</b> may be brought into close contact with the reflecting plate portion <b>18</b> by imparting elasticity to pieces into which the reflecting plate portion <b>18</b> is divided. Further, a metallic spring member coming into close contact with the outer circumferential portion <b>83</b> of the lamp device body <b>34</b> may be separately provided so that heat can be conducted.

0153Next, <figref idref="DRAWINGS">FIG. 15</figref> is a cross sectional view of a lighting fixture according to a seventh embodiment.

0154Screw engaging portions <b>94</b> are used as a thermal conduction connection unit for thermally conductively connecting the substrate attachment portion <b>39</b> side of the lamp device body <b>34</b> to the cap portion <b>38</b> side of the lamp device body <b>34</b>. That is, a screw portion <b>95</b> is formed at the outer circumferential portion <b>83</b> of the cap side metallic part <b>81</b>, and a screw portion <b>96</b> for engaging with the screw portion <b>95</b> of the cap side metallic part <b>81</b> is formed at a circumferential edge portion of the light source side metallic part <b>82</b>.

0155Also when a screw-engagement structure is used as a thermal conduction connection unit, heat can be efficiently conducted from the substrate attachment portion <b>39</b> side to the cap portion <b>38</b> side.

0156Moreover, it is allowed that the lamp device body <b>34</b> is vertically divided by a dividing line in a height direction passing the center of the lamp device body <b>34</b> and pieces of the divided lamp device bodies are joined to each other by screw-clamping or the like. In this case, the substrate attachment portion <b>39</b> side and the cap portion <b>38</b> side are integrally constructed as the thermal conduction connection unit, so that heat can be efficiently conducted from the substrate attachment portion <b>39</b> side to the cap portion <b>38</b> side.

0157Next, <figref idref="DRAWINGS">FIG. 16</figref> is a side view of a lamp device and <figref idref="DRAWINGS">FIG. 17</figref> is across sectional view of the lighting fixture, according to an eighth embodiment.

0158The flat substrate attachment portion <b>39</b>, to which the light-emitting module substrate <b>50</b> is thermally conductively attached, is formed on the lower face of the cap portion <b>38</b> on the lamp device body <b>34</b>, and the housing portion <b>40</b> for housing the lighting circuit <b>37</b> is formed inside the projection portion <b>42</b> of the cap portion <b>38</b>. The lamp pins <b>44</b> are connected to the lighting circuit <b>37</b> in a state that grooves are formed on the substrate attachment portion <b>39</b> and lead wires for connecting the lamp pins <b>44</b> to the lighting circuit <b>37</b> are arranged on the grooves. A part or whole of the projection portion <b>42</b> on the lamp device body <b>34</b> is divisionally formed so that the lighting circuit <b>37</b> can be housed in the housing portion <b>40</b>.

0159By attaching the lamp device <b>14</b> to the socket device <b>13</b>, the contact face <b>41</b> of the cap portion <b>38</b> of the lamp device <b>14</b> is thermally conductively brought into close contact with the fixture body <b>12</b>. In this case, opening portions are formed in the fixture body <b>12</b> in accordance with positions of the lamp pins <b>44</b> of the lamp device <b>14</b>, the socket device <b>13</b> is arranged so as to face the opening portions, and the lamp pins <b>44</b> can be attached to the socket device <b>13</b> without coming into contact with the fixture body <b>12</b>.

0160Since the substrate attachment portion <b>39</b> side and the cap portion <b>38</b> side are integrally constituted as the thermal conduction connection unit, heat can be efficiently conducted from the substrate attachment portion <b>39</b> side to the cap portion <b>38</b> side.

0161Heat conducted to the cap portion <b>38</b> is efficiently conducted to the fixture body <b>12</b> with which the contact face <b>41</b> of the cap portion <b>38</b> comes into contact, and can be efficiently radiated.

0162Moreover, the lighting circuit <b>37</b> may be arranged on the lower face side of the lamp device body <b>34</b> together with the LEDs <b>35</b>. In this case, it is unnecessary to provide the housing portion <b>40</b> for housing the lighting circuit <b>37</b> in the lamp device body <b>34</b> and to divisionally form the lamp device body <b>34</b>, and the lamp device body <b>34</b> can be simplified.

0163<figref idref="DRAWINGS">FIG. 18</figref> is a cross sectional view of a lighting fixture and <figref idref="DRAWINGS">FIG. 19</figref> is a perspective view of the disassembled lamp device, according to a ninth embodiment.

0164The cap portion <b>38</b> of the lamp device <b>14</b> includes a base <b>101</b>, a cover <b>102</b> attached to the base <b>101</b> and a pair of lamp pins <b>44</b> projecting from the cover <b>102</b>.

0165The base <b>101</b> is made of, for example, metal such as aluminum excellent in thermal conductivity, and constituted by integrally forming the flat disk-shaped (annular) substrate attachment portion <b>39</b>, the cylindrical projection portion <b>42</b> projecting from the center of an upper face of the substrate attachment portion <b>39</b> and an annular wall portion <b>103</b> projecting from a circumferential portion of the upper face of the substrate attachment portion <b>39</b> with each other. The annular housing portion <b>40</b> for housing the lighting circuit <b>37</b> is formed between the projection portion <b>42</b> and the wall portion <b>103</b> on the upper face of the substrate attachment portion <b>39</b>. The light-emitting module substrate <b>50</b> is screwed to a lower face of the substrate attachment portion <b>39</b> of the base <b>101</b> so as to come into close face-contact therewith.

0166The cover <b>102</b> is made of insulative synthetic resin and formed in a ring shape. The cover <b>102</b> is attached so as to close an upper face of the housing portion <b>40</b> on the base <b>101</b>.

0167The lighting circuit <b>37</b> has the annularly formed lighting circuit substrate <b>89</b> and is housed and attached into the housing portion <b>40</b> on the cap portion <b>38</b> via an insulating member (not shown).

0168In the state that the lamp device <b>14</b> is attached to the socket device <b>13</b>, the projection portion <b>42</b> of the lamp device <b>14</b> is inserted into the connection hole <b>22</b> of the socket device <b>13</b>, and the end face <b>43</b> of the projection portion <b>42</b> is thermally conductively brought into contact with the flat plate portion <b>17</b> of the fixture body <b>12</b>. Here, it is allowed that a plurality of slits for dividing a part of the flat plate portion <b>17</b> of the fixture body <b>12</b> are provided in the flat plate portion <b>17</b> so as to impart elasticity to small pieces of the divided flat plate portion <b>17</b> and the small pieces are thermally conductively brought into contact with the end face <b>43</b> of the projection portion <b>42</b>. Alternatively, it is allowed that a metallic spring member to be brought into close contact with the end face <b>43</b> of the projection portion <b>42</b> is separately provided so that the flat plate portion <b>17</b> is thermally conductively brought into contact with the end face <b>43</b>.

0169When the LEDs <b>35</b> of the lamp device <b>14</b> are lit, heat generated by the LEDs <b>35</b> is efficiently conducted from the light-emitting module substrate <b>50</b> to the substrate attachment portion <b>39</b> of the base <b>101</b> of the cap portion <b>38</b> and efficiently conducted to the projection portion <b>42</b> formed integrally with the substrate attachment portion <b>39</b> of the base <b>101</b>. The heat conducted to the projection portion <b>42</b> is efficiently conducted from the end face <b>43</b> of the projection portion <b>42</b> to the fixture body <b>12</b> and radiated into air.

0170Therefore, heat generated by the LEDs <b>35</b> and conducted to the substrate attachment portion <b>39</b> of the base <b>101</b> can be efficiently conducted to the projection portion <b>42</b> formed integrally with the substrate attachment portion <b>39</b>, concentrated to the projection portion <b>42</b> and efficiently made to escape the same from the projection portion <b>42</b> to the fixture body <b>12</b>, and heat radiation performance can be improved.

0171On the other hand, the heat conducted to the substrate attachment portion <b>39</b> of the base <b>101</b> is also efficiently conducted to the wall portion <b>103</b> formed integrally with the substrate attachment portion <b>39</b>, and radiated from the wall portion <b>103</b> into air. Therefore, radiation performance of heat generated by the LEDs <b>35</b> can be improved.

0172Accordingly, the lamp device <b>14</b> of the ninth embodiment obtains sufficient heat radiation performance, can restrict the temperature of the LEDs <b>35</b> from rising, and can prevent the LED <b>35</b> from being thermally deteriorated and having a short life and, in some cases, light-emitting efficiency from being lowered.

0173Next, <figref idref="DRAWINGS">FIG. 20</figref> is a cross sectional view of a lighting fixture according to a tenth embodiment.

0174In the lamp device <b>14</b>, the projection portion <b>42</b> of the base <b>101</b> of the cap portion <b>38</b> is solidly formed in a columnar shape. In the case where the lamp device <b>14</b> is constituted as described above, the contact area between the projection portion <b>42</b> and the substrate attachment portion <b>39</b> is increased and thermally conductive efficiency is raised, and thus heat generated by the LEDs <b>35</b> is easily conducted from the light-emitting module substrate <b>50</b> to the end face <b>43</b> of the projection portion <b>42</b>. Therefore, thermal conductivity from the substrate attachment portion <b>39</b> to the projection portion <b>42</b> can be improved, and, consequently, radiation performance of heat generated by the LEDs <b>35</b> can be further improved.

0175Next, <figref idref="DRAWINGS">FIG. 21</figref> is a perspective view of a lighting fixture according to an eleventh embodiment.

0176An exhaust hole <b>106</b> is formed in the flat plate portion <b>17</b> of the fixture body <b>12</b>, and a fan <b>107</b> for discharging air in the fixture body <b>12</b> from the exhaust hole <b>106</b> to the outside is arranged on the flat plate portion <b>17</b>.

0177A plurality of vents <b>108</b> for making an outer peripheral face of the socket device body <b>21</b> communicate with an inner peripheral face of the insertion hole <b>22</b> are provided in the socket device <b>13</b>.

0178Action of the fan <b>107</b> generates an air flow that air under the fixture body <b>12</b> is sucked into the fixture body <b>12</b> from the opening portion <b>19</b> of the lower face of the fixture body <b>12</b>, passes through the plurality of vents <b>108</b> of the socket device <b>13</b>, flows upward through a gap between the inner peripheral face of the insertion hole <b>22</b> and the projection portion <b>42</b>, which is inserted into the insertion hole <b>22</b>, of the lamp device <b>14</b>, and is discharged upward from the exhaust hole <b>106</b> of the fixture body <b>12</b>.

0179The air flow allows heat conducted to the projection portion <b>42</b> to be efficiently radiated into air, and, consequently, radiation performance of heat generated by the LEDs <b>35</b> to be improved.

0180Next, <figref idref="DRAWINGS">FIG. 22</figref> is a perspective view of a lighting fixture according to a twelfth embodiment.

0181Fins <b>109</b> are provided on projection portion <b>42</b> of the lamp device <b>14</b> of the eleventh embodiment shown in <figref idref="DRAWINGS">FIG. 21</figref>. The contact area between heat conducted to the projection portion <b>42</b> and air flowing by the action of the fan <b>107</b> is increased by the fins <b>109</b>, and heat radiation performance can be further improved.

0182<figref idref="DRAWINGS">FIGS. 23 to 27</figref> show a lighting fixture according to a thirteenth embodiment, <figref idref="DRAWINGS">FIG. 23</figref> is a perspective view of a disassembled lamp device and socket device, which are detached from each other, of a lighting fixture, <figref idref="DRAWINGS">FIG. 24</figref> is a plan view of the lamp device, <figref idref="DRAWINGS">FIGS. 25(</figref><i>a</i>) and <b>25</b>(<i>b</i>) are partial cross sectional views each showing a relationship between the lamp pin of the lamp device and a power supplying portion of the socket device. <figref idref="DRAWINGS">FIGS. 26(</figref><i>a</i>) and <b>26</b>(<i>b</i>) are partial cross sectional views each showing a relationship between a signal terminal of the lamp device and a signal transmitting portion of the socket device, and <figref idref="DRAWINGS">FIG. 27</figref> is a circuit diagram of the lighting fixture.

0183As shown in <figref idref="DRAWINGS">FIG. 23</figref>, the lighting fixture <b>11</b> is a downlight and includes a fixture body (not shown), the output adjustment type socket device <b>13</b> attached to the fixture body, and the lamp device <b>14</b> which is attachable to/detachable from the socket device <b>13</b> and has an output adjusting function.

0184On the lower face of the socket device body <b>21</b> of the socket device <b>13</b>, the pair of socket portions <b>24</b> are formed symmetrically with respect to the center of the socket device body <b>21</b>. As shown in <figref idref="DRAWINGS">FIG. 25</figref>, the connection hole <b>25</b> for power supply is formed in the socket portion <b>24</b>, and a power supplying bracket <b>111</b> as a power supplying portion for supplying power to the lamp device <b>14</b> is arranged at the inner side of the connection hole <b>25</b>. The connection hole <b>25</b> is an arc-shaped oblong hole concentric with the socket device body <b>21</b>, and the enlarged diameter portion <b>26</b> is formed at one end of the connect ion hole <b>25</b>. The power supplying bracket <b>111</b> is arranged on a side portion of the other end side of the connection hole <b>25</b> at a position of being not touched from the outside of the connection hole <b>25</b>.

0185As shown in <figref idref="DRAWINGS">FIG. 23</figref>, in the lower face of the socket device body <b>21</b>, a pair of signal connection holes <b>112</b> are formed so as to be orthogonal to the pair of socket portions <b>24</b> and symmetric with respect to the center of the socket device body <b>21</b>. As shown in <figref idref="DRAWINGS">FIG. 26</figref>, a signal bracket <b>113</b> as a signal transmitting portion for transmitting a signal to the lamp device <b>14</b> is arranged at the inner side of the connection hole <b>112</b>. The connection hole <b>112</b> is an arc-shaped oblong hole concentric with the socket device body <b>21</b>, and a large diameter portion may be provided at one end side of the hole <b>112</b>. The signal brackets <b>113</b> are arranged so that a part thereof enters the connection hole <b>112</b> at the other end side of the connection hole <b>112</b>.

0186Power source wires arranged on the fixture body <b>12</b> are electrically connected to the power supplying brackets <b>111</b>, and signal lines extending from a controller (not shown) or the like are electrically connected to the signal brackets <b>113</b>.

0187As shown in <figref idref="DRAWINGS">FIGS. 23 and 24</figref>, the pair of conductive metallic lamp pins <b>44</b> symmetric with respect to the center of the lamp device <b>14</b> is projected on the contact face <b>41</b> of the cap portion <b>38</b> of the lamp device <b>14</b>. In the lamp pins <b>44</b>, a shaft portion <b>44</b><i>a </i>and the large diameter portion <b>45</b> located at a top end of the shaft portion <b>44</b><i>a </i>are formed. When the lamp device <b>14</b> is attached to the socket device <b>13</b>, the large diameter portion <b>45</b> of each lamp pin <b>44</b> is inserted into the enlarged diameter portion <b>26</b> of each connection hole <b>25</b> of the socket device <b>13</b> as shown in <figref idref="DRAWINGS">FIG. 25(</figref><i>a</i>), the shaft portion <b>44</b><i>a </i>of the lamp pin <b>44</b> is moved to the side opposite from the enlarged diameter portion <b>26</b> in the connection hole <b>25</b> by turning of the lamp device <b>14</b> as shown in <figref idref="DRAWINGS">FIG. 25(</figref><i>b</i>), and thus a peripheral face of the large diameter portion <b>45</b> of the lamp pin <b>44</b> is brought into contact with and electrically connected to the power supplying bracket <b>111</b>, the large diameter portion <b>45</b> is hooked to the edge portion of the connection hole <b>25</b> and the lamp device <b>14</b> is held by the socket device <b>13</b>.

0188A pair of conductive metallic signal terminals <b>115</b> are projected on the contact face <b>41</b> of the cap portion <b>38</b> of the lamp device <b>14</b>, the terminals <b>115</b> being orthogonal to the pair of lamp pins <b>44</b> and symmetric with respect to the center of the lamp device <b>14</b>. The signal terminal <b>115</b> is constituted by a columnar pin. When the lamp device <b>14</b> is attached to the socket device <b>13</b>, each signal terminal <b>115</b> is inserted into one end of each connection hole <b>112</b> of the socket device <b>13</b> as shown in <figref idref="DRAWINGS">FIG. 26(</figref><i>a</i>), moved to the other end side of the connection hole <b>112</b> by turning of the lamp device <b>14</b>, and thus brought into contact with and electrically connected to the signal brackets <b>113</b> as shown in <figref idref="DRAWINGS">FIG. 26(</figref><i>b</i>).

0189The lighting circuit <b>37</b> includes the lighting circuit substrate, a power input side of the lighting circuit substrate and the lamp pins <b>44</b> are electrically connected to each other via lead wires or the like, and a lighting output side of the lighting circuit substrate and the light-emitting module substrate <b>50</b> are electrically connected to each other via lead wires or the like. Further, a control circuit for controlling output of the lighting circuit <b>37</b> is mounted on the lighting circuit substrate, and a signal input portion of the control circuit and the signal terminals <b>115</b> are electrically connected to each other via lead wires or the like.

0190Next, <figref idref="DRAWINGS">FIG. 27</figref> shows a circuit diagram of the lighting fixture <b>11</b>. The lighting fixture <b>11</b> controls light output of the LEDs <b>35</b> of the lamp device <b>14</b>, here, subjects the LEDs <b>35</b> to light control, by a signal transmitted from the outside.

0191The power supplying brackets <b>111</b> of the socket device <b>13</b> are connected to a commercial power source e.

0192Input sides of a diode bridge DB<b>1</b> which is a full-wave rectifier are connected to the lamp pins <b>44</b> of the lamp device <b>14</b>.

0193To output sides of the diode bridge DB<b>1</b>, there are connected a smoothing capacitor C<b>1</b> and a series circuit of a primary winding of a transformer Tr<b>1</b> and an NPN-type transistor Q<b>1</b> as a switching element for output control. The transistor Q<b>1</b> is drive-controlled by a driving circuit, and thus direct current flowing to a secondary side of the transformer Tr<b>1</b> is controlled.

0194A rectifying smoothing circuit including a rectifying diode D<b>1</b> and a smoothing electrolytic capacitor C<b>2</b> are connected to the secondary side of the transformer Tr<b>1</b>, and a plurality of series circuits of resistors R<b>1</b>, R<b>2</b> and R<b>3</b>, the LEDs <b>35</b>, and <b>35</b> and transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b> are connected in parallel to the rectifying smoothing circuit.

0195A series circuit of a resistor R<b>4</b> and an electrolytic capacitor C<b>3</b> are connected between the electrolytic capacitor C<b>2</b> and the resistors R<b>1</b>, R<b>2</b> and R<b>3</b>, and a control circuit <b>117</b> is connected in parallel to the electrolytic capacitor C<b>3</b>. PWM signals are supplied from the control circuit <b>117</b> to bases of the transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b> to PWM-control the transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b>. A light control signal transmitted from the outside is input into the control circuit <b>117</b> through the signal brackets <b>113</b> of the socket device <b>13</b> and the signal terminals <b>115</b> of the lamp device <b>14</b>.

0196Next, action of the lighting fixture <b>11</b> of the thirteenth embodiment will be described.

0197In order to attach the lamp device <b>14</b> having a light control function to the light control-type socket device <b>13</b>, the large diameter portion <b>45</b> of each lamp pin <b>44</b> of the lamp device <b>14</b> is inserted into the enlarged diameter portion <b>26</b> of each connection hole <b>25</b> of the socket device <b>13</b> as shown in <figref idref="DRAWINGS">FIG. 25(</figref><i>a</i>), and, simultaneously, each signal terminal <b>115</b> is inserted into one end of each connection hole <b>112</b> of the socket device <b>13</b> as shown in <figref idref="DRAWINGS">FIG. 26(</figref><i>a</i>). By turning the lamp device <b>14</b> in the attachment direction in this state, as shown in <figref idref="DRAWINGS">FIG. 25(</figref><i>b</i>), the shaft portion <b>44</b><i>a </i>of each lamp pin <b>44</b> is moved to the side opposite from the enlarged diameter portion <b>26</b> in the connection hole <b>25</b>, the large diameter portion <b>45</b> of the lamp pin <b>44</b> is brought into contact with and electrically connected to the power supplying bracket <b>111</b>, the large diameter portion <b>45</b> is hooked to the edge portion of the connection hole <b>25</b>, and the lamp device <b>14</b> is held by the socket device <b>13</b>. At the same time, as shown in <figref idref="DRAWINGS">FIG. 26(</figref><i>b</i>), each signal terminal <b>115</b> is moved to the other end side of the connection hole <b>112</b>, and brought into contact with and electrically connected to the signal brackets <b>113</b>.

0198Accordingly, by attaching the lamp device <b>14</b> to the socket device <b>13</b>, the lamp pins <b>44</b> of the lamp device <b>14</b> are electrically brought into contact with the power supplying brackets <b>111</b> of the socket device <b>13</b>, and power can be supplied from the socket device <b>13</b> to the lamp device <b>14</b>. At the same time, the signal terminals <b>115</b> of the lamp device <b>14</b> are electrically brought into contact with the signal brackets <b>113</b> of the socket device <b>13</b>, and a signal can be transmitted from the socket device <b>13</b> to the lamp device <b>14</b>.

0199By turning on the commercial power source e, current from the commercial power source e is rectified by the diode bridge DB<b>1</b> and smoothed by the smoothing capacitor C<b>1</b>. Current flowing to a primary side of the transformer Tr<b>1</b> is controlled by the transistor Q<b>1</b>, and direct current flowing to the secondary side of the transformer Tr<b>1</b> is controlled so as to have a predetermined value. The direct current flowing through the secondary side of the transformer Tr<b>1</b> is supplied to the LEDs <b>35</b> and lights the LEDs <b>35</b>.

0200Here, the transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b> are PWM-controlled by the control circuit <b>117</b>, and the LEDs <b>35</b> are lit while the transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b> are in an on-period and turned off while the transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b> are in an off-period. Since the LEDs <b>35</b> blink at a high speed although being repeatedly lit and turned off, it appears to a user that the LEDs <b>35</b> are continuously lit.

0201The transistors Q<b>2</b>, Q<b>3</b> and Q<b>4</b> are PWM-controlled and the LEDs <b>35</b> are subjected to light control based on a light control signal which is input into the control circuit <b>117</b> from the outside.

0202Since the lamp pins <b>44</b> for receiving power from the socket device <b>13</b> and the signal terminals <b>115</b> for receiving a signal transmitted from the socket device <b>13</b> are provided on the cap portion <b>38</b>, output of the lighting circuit <b>37</b> is adjusted in accordance with the signal received by the signal terminals <b>115</b> and LEDs <b>35</b> can be subjected to light control.

0203Specifically, since the signal terminals <b>115</b> are connected to the signal brackets <b>113</b> in a state that the lamp pins <b>44</b> are brought into contact with the power supplying brackets <b>111</b>, by attaching the lamp device <b>14</b> to the socket device <b>13</b>, the LEDs <b>35</b> can be subjected to the light control.

0204When a lamp device having no light control function is connected to the socket device <b>13</b> for light control, no light control signal is transmitted from the socket device <b>13</b> side to the lamp device having no light control function, and the lamp device having no light control function is lit at a predetermined output regardless of a light control signal.

0205Since the signal terminals <b>115</b> are projected from the cap portion <b>38</b> of the lamp device <b>14</b> having the light control function, the lamp device <b>14</b> cannot be attached to a non-light control-type socket device.

0206Moreover, as shown in <figref idref="DRAWINGS">FIG. 28</figref> showing a fourteenth embodiment, the pair of signal terminals <b>115</b> arranged on the cap portion <b>38</b> of the lamp device <b>14</b> may be arranged together orthogonally to the pair of lamp pins <b>44</b>. In this case, an advantage can be obtained that the lamp pins <b>44</b> side having high voltage can be separated from the signal terminals <b>115</b> side to which a signal is transmitted and which have low voltage.

0207As shown in <figref idref="DRAWINGS">FIG. 29</figref> showing a fifteenth embodiment, the pair of signal terminals <b>115</b> arranged on the cap portion <b>38</b> of the lamp device <b>14</b> may be projected from a circumferential portion of the projection portion <b>42</b>. In this case, structures corresponding to the connection hole <b>112</b> and the signal brackets <b>113</b> may be provided at the inside of the insertion hole <b>22</b> of the socket device <b>13</b>.

0208As shown in <figref idref="DRAWINGS">FIG. 30</figref> showing a sixteenth embodiment, the pair of signal terminals <b>115</b> arranged on the cap portion <b>38</b> of the lamp device <b>14</b> may be provided on the end face of the projection portion <b>42</b> of the cap portion <b>38</b>. In this case, structures corresponding to the signal brackets <b>113</b> to be connected to the signal terminals <b>115</b> may be arranged at the fixture body <b>12</b> side.

0209Moreover, a signal transmitted to the lamp device <b>14</b> is not limited to a light control signal for subjecting the LEDs <b>35</b> to light control. An RGB signal for adjusting the color of the LED <b>35</b> is usable as the signal transmitted as long as the lamp device <b>14</b> enables color lighting.

0210Moreover, also in the fifth to sixteenth embodiments, similar to the first to fourth embodiments, the end face <b>43</b> of the projection portion <b>42</b> of the cap portion <b>38</b> and the heat radiating body can be pressed against each other in a contact direction by attaching the lamp device <b>14</b> to the socket device <b>13</b>.

INDUSTRIAL APPLICABILITY

0211The present invention is applied to a downlight, a ceiling built-in type lighting fixture, a ceiling direct attachment-type lighting fixture, a suspending-type lighting fixture, a wall front face fixture and other lighting fixtures.

REFERENCE SIGNS LIST

0000<ul id="ul0001" list-style="none"><li id="ul0001-0001" num="0000"><ul id="ul0002" list-style="none"><li id="ul0002-0001" num="0212"><b>11</b> Lighting fixture</li><li id="ul0002-0002" num="0213"><b>12</b> Fixture body as heat radiating body</li><li id="ul0002-0003" num="0214"><b>13</b> Socket device</li><li id="ul0002-0004" num="0215"><b>14</b> Lamp device</li><li id="ul0002-0005" num="0216"><b>21</b> Socket device body</li><li id="ul0002-0006" num="0217"><b>22</b> Insertion hole</li><li id="ul0002-0007" num="0218"><b>30</b> Elastic body as pressing body</li><li id="ul0002-0008" num="0219"><b>34</b> Lamp device body</li><li id="ul0002-0009" num="0220"><b>35</b> LED as light source, semiconductor light-emitting element</li><li id="ul0002-0010" num="0221"><b>37</b> Lighting circuit</li><li id="ul0002-0011" num="0222"><b>38</b> Cap portion</li><li id="ul0002-0012" num="0223"><b>39</b> Substrate attachment portion</li><li id="ul0002-0013" num="0224"><b>42</b> Projection portion</li><li id="ul0002-0014" num="0225"><b>44</b> Lamp pin</li><li id="ul0002-0015" num="0226"><b>50</b> Light-emitting module substrate</li><li id="ul0002-0016" num="0227"><b>55</b> Heat radiating plate as heat radiating body</li><li id="ul0002-0017" num="0228"><b>56</b> Spring as pressing body</li><li id="ul0002-0018" num="0229"><b>60</b> Heat radiating plate as heat radiating body</li><li id="ul0002-0019" num="0230"><b>61</b> Spring as pressing body</li><li id="ul0002-0020" num="0231"><b>67</b> Heat radiating member as heat radiating body and pressing body</li><li id="ul0002-0021" num="0232"><b>71</b> Socket support body</li><li id="ul0002-0022" num="0233"><b>85</b> Screw as thermal conduction connection unit</li><li id="ul0002-0023" num="0234"><b>94</b> Screw engaging portion as thermal conduction connection unit</li><li id="ul0002-0024" num="0235"><b>111</b> Power supplying bracket as power supplying portion</li><li id="ul0002-0025" num="0236"><b>113</b> Signal bracket as signal transmitting portion</li><li id="ul0002-0026" num="0237"><b>115</b> Signal terminal</li><li id="ul0002-0027" num="0238"><b>117</b> Control circuit</li></ul></li></ul>